1. Field of the Invention
This invention relates to a read-only memory which can be constructed in a small size, and more particularly to a read-only memory whose multiplexer unit can be simplified and whose memory-cell matrix unit can accordingly be simplified to thereby greatly reduce the space occupied by the entire chip.
2. Description of the Prior Art
The conventional multiplexer unit has only functioned as the Y decoder for X-Y inputs and has been of the fixed type. The present invention intends to simplify the multiplexer unit in advance by a technique which will hereinafter be described, and thereby reduce the overall size of the device.